Popularity of conspiracy theories reveals how people think

Examining the motivations behind people’s willingness to subscribe to sometimes illogical theories led a US legal scholar to some startling conclusions

By Cass Sunstein / Bloomberg

Conspiracy theories surround us. Witness the reactions on the Internet to the tragic and mysterious disappearance of Malaysia Airlines flight 370. Perhaps North Korea hijacked the plane. Perhaps the Chinese are responsible. Maybe aliens did it.

Or, as an influential legislator in Iran contended to the New York Times, perhaps the US “kidnapped” the lost plane in an effort to sabotage the relationship among Iran, China and Southeast Asia.

Pick your topic: Ukraine, the US National Security Agency, assassinations of national leaders, recent economic crises, the authorship of Shakespeare’s plays — it is child’s play to assemble a host of apparent clues and connect a bunch of dots to support a relevant conspiracy theory.

In recent years, for example, many people in the US have become convinced that the US (or Israel) was responsible for the attacks of Sept. 11, 2001; that the US government concocted HIV/AIDS and that US federal agencies have conspired to hide the association between vaccines and autism.

Why do people accept such theories?

The first explanation points to people’s predispositions.

Some of us count as “conspiracists” in the sense that we have a strong inclination to accept such theories. Not surprisingly, conspiracists tend to have a sense of personal powerlessness; they are also more likely to conspire themselves.

Here is an excellent predictor of whether people will accept a particular conspiracy theory: Do they accept other conspiracy theories?

If you tend to think that the Apollo moon landings were faked, you are more likely to believe that the US was behind the Sept. 11, 2001, attacks. (With a little introspection, many of us know, almost immediately, whether we are inclined to accept conspiracy theories.)

Remarkably, people who accept one theory tend to accept another conspiracy theory that is logically inconsistent with it.

People who believe that Princess Diana faked her own death are more likely to think that she was murdered.

People who believe that Osama bin Laden was already dead when US forces invaded his compound are more likely to believe that he is still alive.

The second set of explanations points to the close relationship between conspiracy theories and social networks, especially close-knit or isolated ones.

Few of us have personal or direct knowledge about the causes of some terrible event — a missing plane, a terrorist attack, an assassination, an outbreak of disease.

If one person within a network insists that a conspiracy was at work, others within that network might well believe it.

Once the belief begins to spread, a lot of people within the network might accept it as well, on the theory that a spreading belief cannot be wrong.

And once that happens, “confirmation bias” tends to kick in, so that people give special weight to information that supports their view. They also treat contradictory information as irrelevant or perhaps even as proof of conspiracy. (Why would people — “they” — deny it if it were not true?)

A third explanation emphasizes how humans are inclined to react to terrible events. Such events produce outrage, suspicion and fear.

Sometimes the perpetrator is self-evident, as in the case of many terrorist attacks, but if there is no clear perpetrator — as with a missing plane, a child’s disability or the outbreak of a disease — people might go hunting for the malicious agent behind it all.